double四舍五入

public static void main(String args[]){
        double k = 1024;
        double s = 4170650;
        double e = (s/k)/k;
        System.out.println(getRoundDouble(e));
    }

    //四舍五入
    private static Double getRoundDouble(double unroundedValue ) {
        // TODO Auto-generated method stub
        double intPortion = Math.floor( unroundedValue );
        double unroundedDecimalPortion = ( unroundedValue - intPortion );
        double roundedDecimalPortion = Math.round( unroundedDecimalPortion * 100 );
        roundedDecimalPortion = roundedDecimalPortion / 100;
         double total = intPortion + roundedDecimalPortion;
        return new Double( total );

    }